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DOE OSTI · 1295348

Materials Data on Na4FeO5 by Materials Project

Abstract

Na4FeO5 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are nine inequivalent Na sites. In the first Na site, Na is bonded to six O atoms to form distorted NaO6 octahedra that share corners with six NaO6 octahedra, edges with nine NaO6 octahedra, and edges with three FeO5 square pyramids. The corner-sharing octahedra tilt angles range from 8–24°. There are a spread of Na–O bond distances ranging from 2.36–2.41 Å. In the second Na site, Na is bonded to six O atoms to form distorted NaO6 octahedra that share corners with four NaO6 octahedra, corners with two equivalent FeO5 square pyramids, edges with ten NaO6 octahedra, and edges with two equivalent FeO5 square pyramids. The corner-sharing octahedra tilt angles range from 13–25°. There are a spread of Na–O bond distances ranging from 2.30–2.71 Å. In the third Na site, Na is bonded to six O atoms to form distorted NaO6 octahedra that share corners with five NaO6 octahedra, corners with two equivalent FeO5 square pyramids, edges with nine NaO6 octahedra, and edges with two FeO5 square pyramids. The corner-sharing octahedra tilt angles range from 8–35°. There are a spread of Na–O bond distances ranging from 2.40–2.73 Å. In the fourth Na site, Na is bonded to six O atoms to form distorted NaO6 octahedra that share corners with five NaO6 octahedra, corners with two equivalent FeO5 square pyramids, edges with nine NaO6 octahedra, and edges with two equivalent FeO5 square pyramids. The corner-sharing octahedra tilt angles range from 10–37°. There are a spread of Na–O bond distances ranging from 2.34–2.81 Å. In the fifth Na site, Na is bonded to six O atoms to form distorted NaO6 octahedra that share corners with four NaO6 octahedra, corners with two equivalent FeO5 square pyramids, edges with ten NaO6 octahedra, and edges with two equivalent FeO5 square pyramids. The corner-sharing octahedra tilt angles range from 8–18°. There are a spread of Na–O bond distances ranging from 2.30–2.85 Å. In the sixth Na site, Na is bonded to six O atoms to form distorted NaO6 octahedra that share corners with six NaO6 octahedra, corners with two FeO5 square pyramids, edges with eight NaO6 octahedra, and edges with two FeO5 square pyramids. The corner-sharing octahedra tilt angles range from 23–38°. There are a spread of Na–O bond distances ranging from 2.34–2.55 Å. In the seventh Na site, Na is bonded to six O atoms to form distorted NaO6 octahedra that share corners with five NaO6 octahedra, corners with two FeO5 square pyramids, edges with nine NaO6 octahedra, and edges with two equivalent FeO5 square pyramids. The corner-sharing octahedra tilt angles range from 8–35°. There are a spread of Na–O bond distances ranging from 2.40–2.70 Å. In the eighth Na site, Na is bonded to six O atoms to form NaO6 octahedra that share corners with five NaO6 octahedra, corners with two FeO5 square pyramids, edges with nine NaO6 octahedra, and edges with two FeO5 square pyramids. The corner-sharing octahedra tilt angles range from 18–38°. There are a spread of Na–O bond distances ranging from 2.34–2.54 Å. In the ninth Na site, Na is bonded to six O atoms to form NaO6 octahedra that share corners with four NaO6 octahedra, corners with six FeO5 square pyramids, and edges with eight NaO6 octahedra. The corner-sharing octahedral tilt angles are 35°. There are a spread of Na–O bond distances ranging from 2.43–2.70 Å. There are two inequivalent Fe sites. In the first Fe site, Fe is bonded to five O atoms to form FeO5 square pyramids that share corners with eight NaO6 octahedra and edges with eight NaO6 octahedra. The corner-sharing octahedra tilt angles range from 5–72°. There are a spread of Fe–O bond distances ranging from 1.79–1.85 Å. In the second Fe site, Fe is bonded to five O atoms to form FeO5 square pyramids that share corners with eight NaO6 octahedra and edges with eight NaO6 octahedra. The corner-sharing octahedra tilt angles range from 3–73°. There are a spread of Fe–O bond distances ranging from 1.80–1.84 Å. There are ten inequivalent O sites. In the first O site, O is bonded in a 6-coordinate geometry to five Na and one Fe atom. In the second O site, O is bonded to five Na and one Fe atom to form ONa5Fe octahedra that share corners with three ONa5Fe octahedra, a cornercorner with one ONa4Fe trigonal bipyramid, edges with five ONa5Fe octahedra, and an edgeedge with one ONa4Fe trigonal bipyramid. The corner-sharing octahedra tilt angles range from 0–12°. In the third O site, O is bonded to five Na and one Fe atom to form distorted ONa5Fe octahedra that share corners with two ONa5Fe octahedra, edges with eight ONa5Fe octahedra, and edges with two equivalent ONa4Fe trigonal bipyramids. The corner-sharing octahedra tilt angles range from 10–11°. In the fourth O site, O is bonded to five Na and one Fe atom to form distorted ONa5Fe octahedra that share corners with two ONa5Fe octahedra, corners with two equivalent ONa4Fe trigonal bipyramids, edges with five ONa5Fe octahedra, and edges with two ONa4Fe trigonal bipyramids. The corner-sharing octahedra tilt angles range from 15–19°. In the fifth O site, O is bonded to five Na and one Fe atom to form distorted ONa5Fe octahedra that share corners with three ONa5Fe octahedra, corners with two ONa4Fe trigonal bipyramids, edges with seven ONa5Fe octahedra, and edges with two equivalent ONa4Fe trigonal bipyramids. The corner-sharing octahedra tilt angles range from 11–19°. In the sixth O site, O is bonded to four Na and one Fe atom to form distorted ONa4Fe trigonal bipyramids that share corners with five ONa5Fe octahedra, corners with four ONa4Fe trigonal bipyramids, and edges with two ONa5Fe octahedra. The corner-sharing octahedra tilt angles range from 22–82°. In the seventh O site, O is bonded in a 6-coordinate geometry to five Na and one Fe atom. In the eighth O site, O is bonded to five Na and one Fe atom to form distorted ONa5Fe octahedra that share corners with four ONa5Fe octahedra, corners with three ONa4Fe trigonal bipyramids, and edges with six ONa5Fe octahedra. The corner-sharing octahedra tilt angles range from 0–15°. In the ninth O site, O is bonded to four Na and one Fe atom to form distorted ONa4Fe trigonal bipyramids that share corners with three ONa5Fe octahedra, corners with four ONa4Fe trigonal bipyramids, and edges with five ONa5Fe octahedra. The corner-sharing octahedra tilt angles range from 22–80°. In the tenth O site, O is bonded in a 6-coordinate geometry to five Na and one Fe atom.

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2020-04-29. Materials Data on Na4FeO5 by Materials Project. https://doi.org/10.17188/1295348

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